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The 21Na(p,gamma)22Mg Reaction and Oxygen-Neon Novae

S. Bishop·R. E. Azuma·L. Buchmann·A. A. Chen·M. L. Chatterjee·J. M. D'Auria·S. Engel·D. Gigliotti·U. Greife·M. Hernanz·D. Hunter·A. Hussein·D. Hutcheon·C. Jewett·J. Jose·J. King·S. Kubono·A. M. Laird·M. Lamey·R. Lewis·W. Liu·S. Michimasa·A. Olin·D. Ottewell·P. D. Parker·J. G. Rogers·F. Strieder·C. Wrede
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Abstract

The 21Na(p,gamma)22Mg reaction is expected to play an important role in the nucleosynthesis of 22Na in Oxygen-Neon novae. The decay of 22Na leads to the emission of a characteristic 1.275 MeV gamma-ray line. This report provides the first direct measurement of the rate of this reaction using a radioactive 21Na beam, and discusses its astrophysical implications. The energy of the important state was measured to be E$_{c.m.}$= 205.7 $\pm$ 0.5 keV with a resonance strength $ωγ= 1.03\pm0.16_{stat}\pm0.14_{sys}$ meV.

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S. Bishop, R. E. Azuma, L. Buchmann, A. A. Chen, M. L. Chatterjee, J. M. D'Auria, S. Engel, D. Gigliotti, U. Greife, M. Hernanz, D. Hunter, A. Hussein, D. Hutcheon, C. Jewett, J. Jose, J. King, S. Kubono, A. M. Laird, M. Lamey, R. Lewis, W. Liu, S. Michimasa, A. Olin, D. Ottewell, P. D. Parker, J. G. Rogers, F. Strieder, C. Wrede. 2003-03-13. The 21Na(p,gamma)22Mg Reaction and Oxygen-Neon Novae. https://doi.org/10.1103/physrevlett.90.162501

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